Telephony systems typically route calls based on called party information, such as a destination number, and also sometimes implement routing policies based on load balancing for call traffic management. However, these systems are not sufficiently flexible or efficient in some situations. For example, where users are re-homed from a first sub-network to another sub-network within a carrier's network, destination-based routing with load balancing or other similar policies for traffic distribution and resource management may be inadequate. Moreover, interconnections between two or more carriers may be significantly impacted due to traffic shifts that occur when internal subscriber migrations occur within a carrier's network. Such traffic shifts may typically result in the need for additional trunking infrastructure to cater to the traffic pattern shifts, which can be costly and time consuming to implement.